Railway traffic controlling apparatus



Maida M, 19M. F. H, Mica-:OLSON En* m. v $35,037

RAILWAY TRAFFIC CONTROLLING APPARATUS Filed July l2, 1940 '2 Shams-Sheet l @gz fw.

5' @Qd AMV @www MJU@ ` INVENTORS Hfmz H. clzolfozz and Mff 13, 1941- F. H. NrcI-:oLsoN ETA. 2235,37

RAILWAY TRAFFIC CONTROLLING APPARATUS Filed July l2, 1940 2 Smets-Sheet 2 Patented Mer. le, 1941 2,235,037

UNITED STATES PATENT 1li RAILWAY TRAFFIC CONTROLLING APPARATUS Frank H. Nicholson and Harold W. Bryan, Penn Township, Allegheny County, Pa., assignors to The Union Switch & Signal Company, Swissvale, Pa., a corporation of Pennsylvania Application July 12, 1940, Serial No. Edile?) Z Claims. (C1. 24o-63) Our invention relates to railway trallic congovernor mounted on the train andL operatively trolling apparatus, and more particularly to apconnected by suitable drive mechanism to a train paratus of this type comprising train carried axle or other moving part so that circuit controltrain controlling means governed by energy reling contacts of the governor are actuated at dii- `5 ceived from the track rails. ferent preselected train speeds, a maximum train Train carried train controlling means governed speed being usually prescribed for each of the by alternating current inductively received from different code rates, that is, for each of the difthe track rails is in general use, such alternating ferent `trani-c conditions. The circuit controlling current being preferably coded or periodically incontacts of the speed governor are interposed in terrupted at any one of several different code the circuits for the automatic brake control lo rates according to different traino conditions. equipment in such a manner that an automatic The train carried means includes receiving apapplication of the train brake is effected in the paratus comprising inductors mounted on a train event the train speed exceeds the maximum in inductive relation to the track rails for receive speed prescribed for the traffic condition at which 15 ing electromotive forces corresponding in code to the decoding relays are at the time conditioned. the code of the current iiowing in the rails, and When such automatic speed control is provided, it an electron tube amplifier or detector 4to the inis desirable to provide a Warning indication to put or control side of which the inductors are the train operator when the train is operating at connected and to the output side of which a code a speed above the maximum permissible speed 0 following relay is connected for operation of the and an automatic brake application may be ef- 20 relay at a rate corresponding to the code rate of fected so that the train operator may reduce the the track rail current. Such code following relay train speed by e manuel eppleeton 0f the brakes controls a group `of decoding relays through the or by shutting off the power or by both shutting medium of tuned circuits or filters, suon tuned off the power and makina a manual application circuits or filters being proportioned to selectively of the brakes, and in that way suppress an auto- 2 energize the decoding relays at a condition difmatic brake application and ret-ein full control ferent for each code rate at which the code folof the train.

lowing relay is operated. The decoding relays Furthermore, it has been pl'ODOSed fel SllCh are used in turn `to selectively govern a cab signal train control systems to provide electrical cutand train brake control equipment with the reout means Whcrewith the train carried equipsult that a particular signal aspect is displayed ment may be placed at an inactive or cut-out and a preselected train brake control ls effected condition when the train moves into a territory lor each of the different traflic conditions for Where the track rails are not supplie-d With the which a code rate is assigned. While alternating necessary train control current, and which eleccurrent of 1.00 cycles per second is preferably trical cut-out means permits the automatic train 30 used alternating current of some other frequency control apparatus to be restored to an active conor impulses of direct current may be used by pro dition When the train moves from such nontrain portioning the receiving apparatus for response control territory back to a territory where the to such currents. It is common practice to emtrack rails are supplied with the necessary curploy the code rates of 180, 120 and 75 cycles per rent. Also when the vehicle on which the train 40 minute to reflect clear, approach medium and control apparatus is mounted is a motive power approach traffic conditions, respectively, a fourth unit equipped With IIlOtVe DOWGI COltlOl eppetraflic condition of slovv speed or caution being ratus for operating such vehicle either end rst, reliected by the absence lof such coded current. inductors are located at each end of the vehicle the decoding relays it is customary to interlock provided Whereivith only the inductors at the the manual brake control equipment with the auleading end of the vehicle are rendered effective. tometle brake control equipment governed by the Accordingly, a fea-ture of our invention is the ,decoding relays, and to require a suitable acprovision of novel and improved train carried 00 knowledgment on the part of a train operator train control apparatus for a four-indication 50 of a change to a more restrictive control condifour-speed control train control system. tion in order to prevent application of the brakes Another feature of our invention is the pro* automatically. vision in train carried train control apparatus Speed control equipment may also be provided, of the type here contemplated of novel and imsuch speed control equipment comprising a speed proved speed Warning indication means which is i When brake control equipment is governed by ahead of the Wheels and directional means is 4" t actuated when the train is above the authorized speed and which means also includes a poweroff" switch circuit controller eiTective when operated because the train has exceeded the authorized speed to remove power from the master controller of the vehicle, thereby preventing the train operator from using power to accelerate to a higher speed.

Again, a feature of our invention is the provision of novel and improved timing means wherewith a delay time equal to the slow release eriod of a relay is inserted between the speed warning indication and the automatic application of the brakes and suppression of such automatic application of the brakes may be effected by the train operator taking suitable action to reduce the train speed.

Another feature of our invention is the provision in train carried train control apparatus of the type here involved of a novel and improved acknowledging circuit arrangement Wherewith acknowledgment of the most restrictive indication only is required.

An additional feature of our invention is the provision of novel and improved electrical cutout means wherewith the train carried train control apparatus is automatically placed at a cut-out or inactive condition when the train moves to non train control territory and is automatically restored to its active condition when the train again enters train control territory.

Also a feature of our invention is the provision of novel means wherewith the electrical cut-out means may be manually operated by the cooperation of two members of the train crew.

Also a feature of the invention is the provision oi a novel circuit arrangement for controllingr the timing relay through contacts of a power-off switch so that automatic release of an automatic brake application is prevented and the same procedure followed in suppression of an automatic brake application must be followed to reenergize the brake control magnet valve and permit the release of an automatic brake application.

The above features of our invention as well as other advantages which will become apparent as the specication progresses are attained by providing the usual train carried train control apparatus with a train operated speed governor having a plurality of diiTerent sets or groups or contacts, a speed warning relay which controls over its back contact a speed warning cab signal light, a slow release timing relay which controls over its iront contact the usual brake control magnet valve, and a twin assembly speed warning whistle magnet valve. The magnet of one unit of the warning whistle magnet valve when energized causes a pneumatic power-oil circuit controller or switch to be operated to a closed position and a whistle repeater valve to be actuated to a position where a warning whistle contr-oiled by such repeater valve is silent, and when deenergized permits the power-off circuit controller to be actuated to an open position and the repeater valve to be moved to a position where the warning whistle is sounded. The magnet of this one unit is energized over a circuit having a plurality of multiple circuit paths each of which paths includes a front contact of a particular decoding relay, a contact of the speed governor contact group that corresponds to the same code rate as that at which such decoding relay is energized, and a resistor. The timing relay is connected in multiple with the magnet of this one unit over contacts of the power-off switch controller. The warning relay is connected across the resistors over multiple circuit connections each of which connections includes a contact of the speed governor contact group having a Contact interposed in the correspending circuit path. Hence the warning relay is energized due to the voltage drop across the resistor interposed in the circuit path over which the magnet of this one unit and the timing relay are at the time energized. Thus when the train exceeds the speed prescribed for the tralc condition at which a particular' decoding relay is selected, the warning relay and warning magnet valve are deenergized to eiTect a warning visual signal and a warning whistle but a delay time equal to the slow release period of the timing relay is interposed between the establishment of such warning indications and an automatic brake application.

Suppression of an automatic brake application is effected by providing an alternative circuit for the brake control magnet valve by which such magnet valve may be energized when the timing relay is released and which alternative circuit preferably includes a contact closed at the off position of the mast-er controller of the vehicle in series with a contact of a pneumatically operated suppression switch closed when the manual brake valve is moved to a brake application postion.

The timing relay is also controlled either through a back contact of a relay connected in multiple with the most restrictive cab signal unit or through a front contact of the usual acknowledging relay so that when the most restrictive code rate is received the timing relay is disconnected from the current source and it is necessary for the train operator to make the usual acknowledgment of such restrictive indication and pick up the acknowledging relay in order to reconnect the timing relay to the current source.

rThe second unit of the speed warning whistle magnet valve controls the usual acknowledging whistle.

For automatic electric cut-out of the train control apparatus when the train moves to non train control territory, an additional tuned circuit and decoding relay are provided. This additional tuned circuit is adjusted for response to a code rate materially diierent from the 180. 12o and 75 traino controlled code rates and which may be. for example, of the order of 240 cycles per minute. When current of the 240 code rate is received from a special track circuit located adjacent the point where the train passes to non train control territory and the special cut-out decoding relay is energized and picked up such cut-out decoding relay is retained energized by a stick circuit controlled over back contacts of the traiic controlled decoding relays. Such special cut-out decoding relay when picked up completes special circuits for the timing relay, warning relay and the magnet valve of the Iirst unit of the speed warning whistle magnet valve, and also completes a circuit for a special cab signal unit to indicate operation of the train outside of train control territory. A manually operable cut-out switch is located at a point remote from the usual acknowledging switch and a circuit is provided for picking up the special cut-out decoding relay by a local circuit over contacts controlled by both the cut-out switch and the usual acknowledging switch, so that when two members of the train crew, one at the cut-out switch and one at the acknowledging switch, operate these two switches at the same time the special cut-out relay is picked up to establish the cut-out condition of the train control apparatus. An indication light is provided near the cut-out switch to indicate to the operator thereof the position of the usual acknowledging switch.

To effect directional control a directional circuitl controller is mounted on the vehicle and provided with a contact over which only the train carried inductors at the leading end of the vehicle are connected to the input side of the amplifier. Preferably, such directional circuit controller is automaticaly governed by pneumatic relays connected to the train control air pressure supply pipe in the manner covered b-y a copending application, Serial No. 345,127, iiled July l2, 1940, by W. A. Oehlschlager for Railway traflic controlling apparatus, and wherewith the pneumatic relay corresponds to the end from which the vehicle is to be operated only if supplied with pressure.

We will describe one form of apparatus embodying our invention, and will then point out the novel features thereof in claims.

The accompanying drawings when taken together with Fig. 1a. placed at the left of Fig. 1b are diagrammatic views showing a preferred form of apparatus embodying our invention when used with train carried apparatus of a fourindication four-speed control train control system.

Referring to the drawings, a first pair of inductors 2a. and 2b are mounted at one end of a railway vehicle on which the apparatus of the drawings is mounted, in inductive relation to the track rails Ia and Ibi, respectively, and a second pair of inductors 3a and 3b are mounted at the other end of the vehicle in inductive relation to the track rails Ia and Ib, respectively. It is to be understood that the vehicle on which these induotors are mounted is to function as the motor unit of the train and is provided with a master controller, a manual brake valve and other necessary power equipment at each end of the vehicle for operation of the vehicle either end iirst. The inductors of each pair are connected together in the usual manner and are adaptable of being included in the input or control circuit of an ampliiier AM by means of a contact member of a directional circuit controller DCC, the arrangement be ing such that when contact member 4 is actuated to a left-hand position to close a contact 4-5, the inductors 2a and 2b are connected to the amplifier AM and when the contact member 4 is moved to a right-hand position to close a contact 4 6 the inductors 3a and 3b are connected to the amplifier AM.

The directional circuit controller` DCC is pneumatically actuated. Whenthe usual cut-out valve CVI located at one end of the vehicle, that is, at the same end of the vehicle as inductors 2a and 2b are mounted, is turned to supply air pressure to the train control supply pipe 3|, through. a check valve 'I, pressure is supplied to the diaphragm chamber of a pneumatic relay 8 and contact meinbers 4, 9 and if! of controller DCC are actuated lto the; left-hand position as viewed in the drawcode rate.

connected to the amplifier over contact member 4. The contact members 9 and I0 of controller DCC are used to control the connections of a current source such yas a generator G and battery I3 to terminals B32 and C, and from which terminals current is taken for the various circuits. Generator G is driven by a motor CM and is arranged to supply current of a convenient voltage, such as 32 volts. Battery I 3 serves as a stand-by current source. Hence when the vehicle is to be operated with the end at which inductors 2a, and 2b are mounted as the leading end and the cut-out valve CVI located at the same end of the vehicle is set to supply air pressure to the train control supply pipe 3 I the directional controller DCC is operated to the position where inductors 2a` and 2h are connected to the amplifier but that when the vehicle is to be operated with the other endy first and the cut-out valve CV2 is set to supply pressure to the train control supply pipe 3|, the directional controller DCC is operated as required to connect the inductors 3a and 3b to the amplifier. Also, energy for the various circuits is applied to terminals B32 and C when either relay 3 or I2 is supplied with pressure.

The amplifier AM may be any one of several well-known forms and is shown conventionally. A code following relay MR is connected to the output side of amplifier AM and is operated in the-well-known manner at a rate corresponding to the code rate of the current flowing in the track rails and picked up from the track rails by the inductors.

Code following relay MR controls the usual three decoding relays A, R and L in the wellknown manner and it is sufcient for the present application to point out that when relay MR is operated, direct current is supplied over contact member I4 of relay MR first to one half and then to the other half of primary winding I of a decoding transformer TI a-nd electrcmotive forces of a frequency corresponding to the rate at which relay MR is operated are in turn applied to tuned circuits I E and 21, the arrangement being such that relay A which is coupled to circuit I5 is effectively energized and picked up only when relay MR is operated at the 180 code rate and relay R which is coupled to circuit 2"I is energized and picked up when relay MR is operated at the 120 The electrcmotive forces` induced in secondary winding I8 of decoding transformer TI are rectiiied at contact member IIS of relay MR and unidirectional current is supplied to decoding relay L to effectively energize and pick up relay L when relay MR is operated at either the 180, 120 or 75 code rate. As here shown the decoding relay R is also provided with an alternative energizing circuit which includes terminal B32 of the current source, front contact 20 of relay A, a resistor 2l, winding of relay R, front contact 22 of relay A, wireC I ,back contact 23 of a relayPto be later described, and terminal C of the current source. It follows that when current of the 180 code rate is picked up from the track rails decoding relays A and L are energized due to the operation of relay MR and relay R is energized and picked up due to its alternative circuit; when current of 120 code rate is picked up from the track rails decoding re- 4 Cil across primary winding l5 of decoding transformer Tl and is tuned to resonance at the frequency of the electromotive force eilected by operation of relay MR at some rate materially different from the traffic controlled rates of 180, 120 and '75. Such additional code rate may, for example, be of the order of 240 cycles per minute. A cut-out decoding relay P is coupled to the tuned circuit i9 an is eectively energized and picked up only when relay MR is operated at the code rate of 240. Decoding relay L may be picked up at the special code rate of 240 cycles per minute but the energizing of the traffic controlled decoding relay L at such time serves no useful function, as will appear later in the specication.

The form of tra-ckway apparatus for supplying to the rails current coded at different code rates in response to different tramc conditions is immaterial and it may be that covered by the United States Letters Patent No. 1,986,679, granted January l, 1935, to L. V. Lewis for Railway traflc controlling apparatus, and wherein alternating current coded at the code rates of 18S, 120 and 80 (75) is supplied to the track rails of a section in response to clear, approach-restricted (approach-medium), and approach traiiic conditions in advance of such track section, respectively, and which current is shunted away from a following train by a leading train.

At a point where a train is to move from train control territory to nontrain control territory, a special track circuit would be provided for snpplying the special 240 code rate for operating the relay P. Speci-al circuits at points where a train moves from train control territory to non train control territory are well-known and the special track circuit for providing the 240 code rate would be in accordance with usual practice since its specific arrangement forms no part of our invention.

Decoding relays A, R and L govern the operating circuits for two cab signals one placed at each end of the vehicle near the position of the train operator. The operating circuits of the two cab signals are arranged in parallel and the cab signal CS located at the same end of the vehicle as inductors 2a and 2b only is shown in the drawings for the sake of simplicity since the second cab signal at the other end of the vehicle is a duplication of cab signal CS and a descrip' tion of the circuits for signal CS is sufficient for an understanding of the circuits for both of such cab signals. Cab signal CS may take different forms and is shown as a color light signal capable of displaying a distinctive aspect for four different traic and speed conditions, a speed warning condition and a cut-out or non-active condition. The four different traiiic and speed condition aspects are displayed by four signal units designated by the reference characters S5, 25, I'I and ll. The speed warning condition is displayed by a signal unit W and the cut-out condition is isplayed by a signal unit NS. Preferably these signal units of cab signal CS when illuminated displayI a distinctive color and in addition the four units 35, 25, El and il display a corresponding numeral. The respective color of these four signal units indicates the traffic condition in advance and the numeral designates the prescribed maximum speed for the corresponding tramo condition. Por example, the signal unit 35 when illuminated displays a green color to indicate clear traffic conditions in advance, and the numeral 35 to indicate a maximum prescribed speed of 35 miles per hour for clear traine conditions. Likewise signal unit 25 when illuminated displays a green over a yellow color and the numeral 25, the green over yellow color indicating approach-medium traic conditions in advance, and the numeral 25 indicating the maximum prescribed speed of 25 miles per hour for approach-medium trailc conditions. Again, illumination of the signal unit I1 displays a yellow color and the numeral I1, the yellow color indicating approach traiiic conditions in advance and the numeral l1 indicating the prescribed maximum speed of 17 miles per hour for approach traflic conditions. The illumination of signal unit Il displays a red color to indicate slow or caution traiiic conditions and the numeral ll to indicate the prescribed maximum speed of 11 miles per hour. It is to be understood, of course, that our invention is not limited to such cab signal indications and train speeds CII for the diierent traic conditions but such cab signal indications and prescribed train speeds have been found useful where dense trac conditions prevail. The color of the indications displayed by signal units NS and W will be referred to later in the specication.

Referring specically to the operating circuits by which the traino controlled decoding relays govern the traffic controlled signal units of cab signal CS, when decoding relay A is picked up in response to the clear 180 code rate an operating circuit can be traced from terminal B32 over front contact 2i! of relay A, wire AI, lamp of signal unit 35 of cab signal CS, wire NA, front contact 22 of relay A, wire Cl, back contact 23 of relay P and terminal C, and the signal unit is illuminated. When relay R is picked up and relay A is released in response to the approachmedium 120 code an operating circuit is formed from terminal B32 over back contact 24 of relay A, front contact 26 of relay R, wire RI, lamp of signal unit 25, wire NR, front contact 28 o1" relay R, back contact 29 of relay A, wire CI and back contact 23 of relay P to terminal C, and signal unit 25 is illuminated. Again when relay L is picked up and relays A and R are released in response to the approach 75 code, an operation circuit extends from terminal B32 over back contacts 25 and 3@ of relays A and R, respectively, back contact 5l of a relay SP to be referred to, front contact 32 of relay L, wire Ll, lamp of signal unit Il', wire NL, front contact 33 of relay L, back contacts 314 and 29 of relays R and A, res ectively, wire Cl and back Contact 23 of relay P to terminal C, and signal unit l1 is illuminated. i

When the train is following another train in the track section and the coded rail current is shunted by the leading train and the decoding relays A, R and L are all released, an operating circuit is formed from terminal B32 over back contacts 213, 3i), 5l and 36 of relays A, R, SP and L, respectively, wire SI, back contact 3l of relay P, wire SK and lamp of signal unit I l to terminal C, and signal unit Il is illuminated. It is to be noted in connection with the operating circuit for signal unit Il that when relay SP is picked up in a manner to later appear, the back contacts 5l and 3'3 of relays SP and L are shunted by a connection completed at front contact of relay SP.

A relay S, an acknowledging relay SP and a manually operable acknowledging switch ACK are associated with the decoding relays. Acknowledging switch ACK is mounted at the same end of the vehicle as cabl signal CS and in a pofio 'sition for convenient operation by the train operator. Relay S is in effect energized in multiple with the slow speed or caution signal unit I I, the left-hand terminal of the winding of relay S being connected to terminal B32 over wire Si and back contacts 24, 30, 5| and 34 oi relays A, R, SP and L, respectively, the same'as signal unit `I I, and the right-hand terminal oi the winding of relay S being connected to terminal C over back contacts 50, 34 and 29 of relays L, R and A, respectively, wire Cl and back contact 23 of relay P. The acknowledging relay SP is preferably of the type capable of being picked up over its back contact and is provided with a pick-up and a stick circuit both of which circuits are governed by the acknowledging switch ACK and 'the decoding relays. The pick-up circuit extends from terminal B32 over back contacts "i4, 3d, 5i and 35 of relays A, R, SP and L, respectively, wire SI, contact 52 of switch ACK when that switch is depressed, wire SPI, a top winding of relay SP, wire NSP and contact 53 of switch ACK when depressed to terminal C. With relay SP picked up and switch ACK returned to its normal position the stick circuit for relay SP is formed from terminal B32, over contact 54 of switch ACK, wire B2, back contact 55 of relay P, back contacts 56, 51 and 58 of relays A, R and L, respectively, front contact 59 of relay SP, lower winding of relay SP, back contacts 5d, 34 and 29 of relays L, R and A, respectively, wire Ci and back contact 23 of relay P to terminal C. Again it is to be noted that front contact @il of relay SP completes a shunt path around back contacts. 5| and 36 of relays SP and L. Thus when slow traiiic conditions prevail, relay S is at once picked up and acknowledging relay SP may be picked up by the operator depressing the switch ACK and then restoring the switch to its normal position. The function of acknowledging relay SP and relay S will appear hereinafter. Since the vehicle is to be operated either end rst, a second acknowledging switch similar to switch ACK is provided at the other end of the vehicle and the circuits for acknowledging relay SP are governed by this second switch in substantially the same manner as switch ACK governs the circuits for relay SP but such second switch is omitted from the drawings for the sake of simplicity.

Automatic application of the train brakes is effected by a brake control magnet valve MV and a brake application valve BA, both of which may be of any one of the several weil-known structures for such devices and may be of the structure disclosed in the aforementioned copending application, Serial No. 345,127, and it is sufficient for this application to point out that when magnet valve MV is energized to close a valve 5t and open a valve 39, pressure is built up on both sides of the piston 4l) of the brake application valve BA and the piston 40 is held at its brake release position by means of the usual biasing spring, but that when magnet valve MV is deenergized to open valve 38 and close valve "i9, the left-hand chamber of the brake application valve BA is exhausted and piston 4@ is forced to its brake application position.

The magnet valve MV is energized over either a normal circuit or an alternative circuit. The normal circuit includes terminal B32, front con.n tact 9| of a timing relay TR to be referred to later, wire M, winding of magnet valve MV, wire NM, front contact d2 of relay TR and terminal 75 C. The alternative circuit includes terminal B32,

contact 54 of acknowledging switch ACK at its normal position, a contact |02 of the master controller of the vehicle located at the same end of the vehicle as cab signal CS and closed only at the power oi'position of the master controller, contact |03 of a suppression switch SR to be later described, wires MI and M, winding of magnet valve MV, wires NM and NMI, a second contact |54 of suppression switch SR, a second contact |55 of the master controller, and terminal C. Suppression switch SR is of the usual pneumatic relay type and is connected to the manual brake control valve in such a manner that pressure is admitted to the diaphragm chamber of switch SR when the manual brake valve is moved to a brake application position and contacts |03 and |434 are closed, but that when the brake valve is moved to a brake release or running position the diaphragm chamber of relay SR is exhausted to atmosphere and contacts |03 and |44 are open. l-Ience magnet valve MV is energized and the brake release position is effected for the automatic brake application valve BA when timing relay TR is energized closing front contacts 9| and 92 and an automatic application of the train brake is effected when timing relay TR is 1released unless the master controller is set at its power oi position and the suppression switch SR is actuated because the manual brake valve has been set at a brake application position.

A pneumatic actuated power off switch controller PS and a speed warning repeater valve PV are controlled by air pressure supplied from the train control supply pipe 3| through one unit of a twin assembly speed warning whistle magnet valve AMV, the power off switch controller PS being also controlled by the slide valve of the brake application valve BA. The specific structures of the three devices PS, PV and AMV form no part of our invention and it is suiiicient to point out that when magnet 6| of a first unit of the magnet valve AMV is energized to close valve S2 and open valve 63 pressure from the train control supply pipe 3| is admitted to pipe t4 leading to the piston chamber of repeater valve PV and also through port 4| of the slide valve of the brake application` valve BA to pipe t5 and thence to the piston chamber of the power oil switch controller PS. Such pressure causes piston 66 of switch controller PS to be forced upward against the force of bias spring Eil and contacts 44, 45, 46 and 41 are raised to a closed position. When magnet 6| of the rst unit of magnet valve AMV is deenergized to open valve 62 and close valve 63, the pressure of the supply pipe 3| is shut off and pipe G4 is connected to an exhaust port with the result that the pressure in the piston chamber of the switch controller PS is exhausted to atmosphere and the contacts 44 to 41, inclusive, are moved under the force of the bias spring 61 to an open` position. Also the piston chamber of switch controller PS is exhausted and the contacts 44 to 41, inclusive, are opened when brake application valve RA is actuated to a brake applying position and connects pipe 85 to an exhaust port. The contacts 44 and 45 are used to govern the circuit of timing relay TR, as will shortly appear, and the contacts 4t and 41 are interposed in the power supply to the master controller of the vehicle so that when contacts and 41 are opened the motive power for the vehicle is interrupted.

Pressure supplied from pipe B4 to the piston chamber of repeater Valve PV forces piston B8 to the right as viewed in the drawings against the force of the bias spring and a valve 59 is closed to blank the supply of pressure from supply pipe 3l to a pipe 'lil leading to a speed warning whistle II located at the same end of the vehicle as cab sign-al CS. Pipe 'i' is connected to an exhaust port by a valve il when pressure is thus applied to piston S8. When the pressure of pipe dil is exhausted, piston 68 of repeater valve PV is forced to the left as viewed in the drawings to close valve 'I1 and open valve 69, and pressure from supply pipe SI flows through pipe I9 to whistle li, and whistle H is caused to sound a warning indication. It is to be seen, therefore, that when magnet @i of the speed warning magnet valve AMV is energized the power 01T switch controller PS is held closed unless the automatic brake application valve BA has been operated, and repeater valve PV is operated to cause the warning whistle li to be silent, but that when magnet Si is deenergized the power oi switch controller PS is operated to its open position to interrupt the motive power and to open the circuit for the timing relay, and repeater valve PV is operated to cause pressure to be supplied to the warning whistle l'I, causing that whistle to sound.

When magnet 'i2 of the other or second unit of the speed warning whistle magnet valve AMV is energized in a manner to later appear to actuate a poppet valve 73 pressure is admitted from supply pipe 3i to a pipe M leading to an acknowledging whistle l5 which is also located at the same end of the vehicle as cab signal CS and whistle l5 is thereby sounded. When magnet 'I2 is deenergized valve 'i3 is actuated to blank the supply oi pressure to pipe 'I4 and the acknowledging whistle 'i6 is silent. The two whistles 1I and 'IG form two audible signals and would be of diierent tones to provide distinctive audible signals. In actual practice whistles II and 16 would be duplicated at the other end of the vehicle, such duplication of whistles being supplied with pressure through pipes branching from pipes 'i0 and 14.

The apparatus also includes a speed governor GV. This speed governor would be operatively connected to a train axle or other moving part through the medium of suitable drive mechanism, several such drive mechanisms being wellknown to the art. This speed governor may, for example, be of the structure covered in the application for Letters Patent of the United States, Serial No. 205,276, filed April 30, 1938 by H. L. Bone and J. W. Livingston for Speed responsive devices.

The speed governor GV is provided with four different groups of contacts, each group consisting of three separate contacts and the contacts of each group of contacts being set for operation at preselected speeds of the vehicle. For example, the contacts 39a, 89h and 80C of the rst group of contacts are set for operation from a biased closed position to an open position at train speeds of the order of 35 miles per hour which is the maximum speed prescribed for clear traiiic conditions. For reasons to shortly appear there is a speed differential between contact Ba and contacts 8&2) and Stic, contact 80a being set to open at 35 miles per hour and contacts 80h and Sile being set to open at 361/4 miles per hour. The contacts Bla, Sib and Sic of the second group of contacts are set for operation from a biased closed position to an open position at train speeds of the order of 25 miles per hour, which speed is the maximum prescribed speed for approach-medium traffic conditions. A speed differential is likewise provided for this group of contacts, contact @la being set to open at 25 miles per hour and contacts Bib and 8Ic being set to open at 26 miles per hour. Again, the contacts tta, 82h and 82o of the third group of contacts are set for operation from a biased closed position to an open position at train speeds of the order of i7 miles per hour, which is the maximum prescribed speed for approach traic conditions; a speed differential being provided with contact set to open at 161/2 miles per hour and contacts 82h and 82C set to open at 171/2 miles per hour. The contacts 83a, 83h and 83u of the fourth group of contacts are set for operation from a biased closed position to an open position at train speeds of the order of 11 miles per hour, which is the maximum prescribed speed for slow or caution traiiic conditions, a speed differential being provided by contact 83a being set to open at 10 miles per hour and contacts 331) and 83C being set to open at l1 miles per hour.

The contacts of each group of contacts of the speed governor GV are interposed with certain contacts of the decoding relays in a circuit which controls magnet valve GI of the rst unit of the speed warning whistle magnet valve AMV, the timing relay TR and a speed Warning signal relay WL. That is, magnet 6i and relays TR and WL are controlled over a circuit having a plurality o1" nrultiple circuit paths each of which circuit paths includes a front contact of a particular one of the decoding relays and the contacts of the speed governor contact group that is assigned to the same traffic condition or code rat-e as that at which that particular decoding relay is energized. When clear traffic conditions 4exist and decoding relay A is picked up in response to the clear 180 code, a circuit can be traced from terminal B32 over contact 54 of acknowledging switch ACK, wire B2, back contact of relay P, front contact 84 of decoding relay A, wire AG, contact Elib of the first contact group of speed governor GV, a resistor AGI, wire SW, winding of magnet 6l, wire NSW, contact 80e of the rst contact group of speed governors GV, front contact 42 of relay A and to terminal C. The winding of relay WL is connected across resistor AGI over a connection that can be traced from the right-hand terminal of the winding of relay WL over wires SWI and SW to the left-hand end of resistor AGI, and from the right-hand end of resistor AGI over contacts BSD and Sila in series and wire B5 to the left-hand terminal of winding of relay WL. Timing relay TR is connected in multiple with the winding of magnet 6I by a connection branching from wire SW over contact 44 of the power oi switch controller PS, either back contact 86 of relay S or front contact 31 of relay SP, winding of relay TR, either back contact 88 of relay S or front contact 89 of relay SP, and contact 45 of the power off switch controller PS to wire NSW. It is to be seen, therefore, that under clear tralic conditions and with decoding relay A picked up the magnet 6I and timing relay TR are energized in parallel over a circuit path including a front contact of relay A, contacts of the rst group of speed governor contacts and resistor AGI, and relay WL is connected across resistor AGI over contacts of the same group of contacts of the speed governor, and is energized due to the voltage drop across resistor AGi. Magnet 6I when energized controls the power oi switch controller PS and repeater Valve PV in the manner already explained and relay TR when energized controls the brake control magnet valve MV as previously explained. Relay WL controls at its hack contact 9U a simple circuit for the warning signal unit W of cab signal CS, the circuit being completed over wire WI. Hence signal unit W is dark as long as relay WL is energized and is illuminated when relay WL is released. It is also to he noted that this circuit path for energizing niagnet BI and relays TR and WL under clear traic conditions is completed at the rst group ci speed governor contacts when the vehicle does not exceed the speed of 35 miles per hour as prescribed -ior clear traflic conditions, and when the speed of 35 miles per hour is reached contact d is opened to deenergize relay WL and when the speed of 361A; miles per hour is reached contacts 8029 and 80C are opened to deenergize magnet 6I and relay TR.

In the event approach-medium tra-flic conditions exist and decoding relay R is picked up and decoding relay A is released, a second circuit path extends from terminal B32 over contact 54 of acknowledging switch ACK, wire Bt, back contact of relay P, back contact il@ of relay A, front contact 93 of decoding relay R, wire RG, contact Bib of the second group of contacts of speed governor GV, a resistor RGI, wire SW, winding of magnet 6I, wire NSW, a second contact BIC of the second group of contacts, front contact 94 of decoding relay R and hack contact 95 of relay A to terminal C. Relay WL is conw nected across resistor RGI over a connection including contacts Bla and 8 Ib of the second group of speed governor contacts as will appear from an inspection of the drawings and relay WL is energized due to the voltage drop across resistor RGI. Timing relay TR is connected in multiple with the winding of magnet 6i over contacts lil and 45 of the power off switch controller PS the same as under clear trai-lic conditions. Again it is to be noted that under approach-medium traffic conditions magnet 6I and relays TR and WLV are energized when the train speed is below 25 mliles per hour, and because of the speed differential when the speed of 25 miles per hour is reached contact Bla opens to deenergize relay WL and when the speed of 26 miles per hour is reached contacts Bib and SIC are opened to deenergize magnet 6I and relay TR.

Under approach traiic conditions and with decoding relay L picked up and relays A and R released, a third circuit path is completed and which circuit path is the same as the second path up to back contact 56 of relay A, thence over back contact 51 of relay R, front contact 96 of decoding relay L, wire LG, contact Mb of the third group of contacts of speed governor GV, a resistor LGI, Wire SW, winding of magnet tI, Wire NSW, a second contact 82C of the third group of contacts, front Contact 9i of decoding relay L, and back contacts 98 and liti of relays R and A, respectively, to terminal C. Relay WL is connected across resistor LGI over a connection which includes contacts 82a and B2b of the third group of speed governor contacts, and tim ing relay TR is connected in multiple with the winding of magnet 6I the same as in the previous cases. It follows that under approach trafc conditions magnet GI and relays TR and WL are energized and picked up as long as the vehicle speed does not exceed that at which the contacts of the third group of ,speed governor contacts are set for operation, but that when the speed of ll/2 miles per hour is reached contact tile is opened to deenergize relay WL and when the speed of 171/2 miles per hour is reached 'contacts t2?) and diie are opened to deenergize magnet @l and relay TR.

Under slow traihc conditions, that is, the most restrictive traido condition, a four-th circuit path is completed for magnet tl and relays TR and WL. This fourth circuit path extends from terminal B32 over loa-ck contacts 24, 2B, 5I and 3.6 of relays A, R, SP and L, respectively, wire SI, iront contact of relay S, wire SG, contact 83h of the fourth group of contacts of speed governor GV, a resistor SGI, wire SW, winding of magnet tl, wire NSW, contact 33o of the fourth gro-up of contacts, hack contact I Il of relay P, and hack contacts Ilil, si; and 95 of relays L, R and A, respectively, to terminal C. If acknowledging relay SP is picked up ,then its front contact lili forms a shunt path around back contact EI of relay SP and back contact 36 of relay L for this fourth circuit path. Relay WL is connected across resistor SG! over contacts 83a and of this fourth group of contacts and is energized due to the voltage drop across resistor SGI, and timing relay TR is connected in multiple with the winding of magnet til as in the previous cases. l-lence under this most restnic tive traine condition when all the decoding relays A, R and L are released, the magnet 6I and relay TR and WL are energized when the train speed is bellow that at which the contact-s of the fourth group of contacts of speed governor GV are set for operation. That is, when the speed ci l0 miles per hour is reached contact 83a is opened to deenergize relay WL and when the speed ci ll miles per hour is reached contacts 33h and lite are open to deenergize magnet 6I and relay TR.

Cut-out decoding relay P, as previously explained, 'is effectively energized and picked up through tuned circuit lli in response Ito opera tion of relay at a 2420 code rate, which code rate is supplied from a special short ytrack section 'located at each point where Ethe vehicle may leave Itrain control territory for non train control territory, `and relay P when picked up automatically eiiects a cut-out condition for the train carried train control apparatus. `Relay P in order to retain the apparatus in Iits cut-out position while the vehicle operates over nontrain control territory, Iis further provided with a stick circuit by which it is retained picked up after a train moves beyond the special track circuit, the traic control decoding relays IA, R and L being, of course, all deenergized and released while the vehicle occupies lncntralin control territory. This stick circuit for relay P involves terminal B32, hack contacts ill, 311i, 5I and 36 of relays A, R, SP and L, respectively, wire SI, front contact it@ oi relay P, wire P12, normal-ly closed contact Irl7 of a manually operable cutout switch CO `to he later referred to, wire PI, resistor litt, winding of relay P, wire NP, front contact It!) of relay P, hack contacts Ill, 98 and liti of relays L, R and A, respectively, and 'terminal C. When cut-out relay P is picked up the NS signal unit of cap signal CSI is illuminated to display a special purple color as Ian indication of the cut-out condition of the apparatus. The operating circuit for signal unit NS branches from wire Pt of the stick circuit of relay P through signal unit NS and joins the stick circuit cf relay P at wire NP. Relay P when picked all) up completes an alternative circuit for energizing magnet of the magnet valve AMV and relay WL in series, this alternative circuit including terminal B32, contact 54 of acknowledging switch ACK, wire B2, front contact Il@ ci relay P, wire 85, winding of relay WL, Wires SW| and SW, winding of magnet 6|, wire NSW and front [contact ||l| of relay P to terminal C. `Since the power off switch controller PS is closed when magnet 6| is energized and since timing relay TR yis connected across wires SW and NSW over contacts M and i5 of controller PS, the timing rel-ay TR is also retained energized when the cutout relay P is picked up.

'In describing the :operation of the apparatus it is to be pointed out that `the relays, valves and signal units are shown in Figs. 1a and lb deenergized and inactive. It will be assumed .that the vehicle is to be operated with the end at which cab signal CS and whistles and 'I5 are located as the leading end. As the trst step in placing the train control apparatus in service cut-ou-t valve CVI is set to supply air pressure-to the train control supply pipe 3|. Pressure is at .the same time supplied to pneumatic relay 3 and directional circuit controller DCC is moved to the left-hand position connecting inductors 2a and 2b to amplifier AM and supplying energy to terminals B32 and C. When valve CVI is operated the operator would also depress acknowledging switch ACK which causes the acknowledging relay SP' 'to be picked up over its previously traced pick-up circuit and then retained picked up over its `previously traced stick circuit when switch ACK is restored to its normal position since the decoding relays A, R and L are now all released. Relay `S is also picked up when energy is applied to terminals B32 and C because the decoding relays are all released. With relay S picked up the magnet valve I6| is energized over the fourth circuit path which includes front contact 99 of relay S, contacts 83h and 83o oi the fourth contact group Eof speed governor GV and resistor SGI, With magnet 5| energized pressure is applied to the piston chamber of repeater valve PV, causing valve 69 to be closed to blank pressure from pipe 3| to pipe 'It and warning whistle Til is silent.

The operator next places the manual brake valve at a brake application position causing suppression switch SR to close contacts |03 and *I0/l and 4brake control magnet valve MV is energized over its alternative circui-t and the automatic brake application valve BA is actuated to its brake release position.

`Since magnet G-I is energized pressure is now suppli-ed to the power off switch PS closing contacts 41|, 45, 4t and 7. The closing of contacts 4B and M applies motive power to the master controller for operating the vehicle, and the closing of contacts 4i and l5 energizes timing relay TR in multiple with magnet 6|, the connection to relay TR being completed at front contacts 37 and 89 of relay SP. Brake control magnet valve MV is now energized over its normal circuit including front contacts 9| and 92 of relay TR and `the operator may move the manual brake valve to the release position.

It is to be noted lthat when energy is lrst applied to yterminals B32 and C, magnet 'l2 of the whistle magnet valve AMV is energized and pressure is supplied from supply pipe 3i! to pipe 74 and the acknowledging whistle 'I6 is sounded. The circuit for magnet valve l2 extends from :terminal B32 over contact 54 of acknowledging switch ACK, wir@ B2, back contacts 55, 5S, 51, 58 and |12 of relays P, A, R, L and SP, respectively, and winding of magnet valve 'l2 to terminal C. When .the operator depresses switch ACK to pick up relay SP magnet valve 'l2 is deenergized and whistle 'It is rendered silent.

Warning relay WL is energized and picked up due to the voltage drop across resistor SGI so that signal unit W is dark. The signal unit however, is illumined since the decoding relays are all released.

The apparatus is now in service and the vehicle can be operated under the control of the train operator.

When the vehicle is moving over a track section under clear traffic conditions and current of the 180 code rate is received, decoding relays A and L are picked up due to operation of the code following relay MR and relay R is picked up by its alternative circuit including front contacts 20 and 22 of relay A. The picking up ofl relays L and R at this time eiiects no particular function and need not be further considered under clear traino conditions. The picking up oi decoding relay A completes the operating circuit for the cab signal unit 35 and that unit displays a clear traffic condition and a speed limit of 35 miles per hour. Decoding relay A also completes at its front contacts S4 and 42 the first circuit path by which magnet 5l of the speed warning magnet valve AMV and relays TR and WL are energized, such circuit path including the first group of contacts of the speed governor GV. With timing relay TR picked up closing front contacts Qi and d2 the brake control magnet MV is retained energized and the brake application valve BA occupies its brake release position. Thus the vehicle may under clear traffic conditions operate at speeds up to 3.5 miles an hour under manual control of the train operator. Assume that the vehicle exceeds the speed of 35 miles per hour, contact 88a of the first group of speed governor contacts is opened, and rela-y WL is deenergized to cause the warning signal W to be illuminated. If the operator reduces the speed the warning signal W goes out when contact Stia. is reclosed. If the speed continues to increase and reaches 361/4 miles per hour, contactsy 89h and 80o are opened to deenergize magnet 5I and relay TR. Magnet valve 6| at once causes operation of the power off controller PS to open at contacts i and t? the connection for the motive power so that the train operator cannot apply power to increase the speed of a vehicle. The repeater valve PV is also operated to cause the warning signal 'it to be sounded. Timing relay TR is not released to open front contacts t and 92 until the end of its slow release period and hence an automatic brake application is not eifected until the end of the slow release period of timing relay TR subsequent to the sounding of the warning whistle li. This slow release period of timing relay TR may be of the order of two and one-half seconds. If the operator acts to move the master controller to its power ofi position closing contacts` i02 and |55 and also places the manual brake valve at a brake application position to operate suppression switch SR and close contacts |63 and |56 during this delay period of two and one-half seconds before timing relay TR is released to actuate magnet valve MV, the magnet valve MV is retained energized over its alternative circuit `and automatic application of the train brake is suppressed. Hence the warning signal indication W is iirst displayed and the warning whistle is next sounded to warn the operator to reduce the speed and an automatic brake application is eiected after two and one-half seconds unless the operator takes suitable steps to reduce the train speed.

In the event the vehicle is moving over a track section for which approach-medium trariic conditions in advance prevail and current of the code rate of 120 is received so that decoding relays R and L are picked up and decoding relay A is released, the approach-medium signal unit 25 of the cab signal is displayed. Magnet valve 0| and relays TR and WL are now energized over the second circuit path which includes the second group of contacts of the speed governor, and the vehicle may be operated at speeds up to 25 miles per hour under manual control. If the vehicle speed exceeds 25 miles per hour to open contact llla of the second group of contacts of the speed governor, relay WL is deenergized and the warning signal W is displayed. Ii the train speed continues to increase and exceeds 20 miles per hour, contacts ulb and 8|c are opened to deenergize magnet 6| and relay TR. Warning whistle 'Il is operated the same as previously explainedand an automatic brake application is effected at the end of the two and one-half seconds slow release period of relay TR unless the operator acts to shut ofi power causing contacts |02 and` |05 to be closed and places the manual brake valve at a brake applying position causing con,- tacts |03 .and |04 of the suppression switch SR to close so that the magnet valve MV is energized over its alternative circuit. As soon as the speed of the vehicle is reduced to less than 25 miles per hour so that the second group of speed governor contacts are reclosed magnet valve 6| and relays WL and TR are reenergized and the vehicle can then be operated under manual control as previously explained.

When the vehicle passes into a track section having approach traffic conditions and current of the 'l5 code is received causing decoding relay L to be picked up and decoding relays R and A to be released the approach cab signal unit l'lis illuminated to display an approach calo signal and to indicate the speed limit of 1'7` miles per hour for the vehicle. Magnet valve 0| and relays TR and WL are now energized over the third circuit path which includes the third group of speed governor contacts. In the event the vehicle exceeds the speed of 161/2 miles per hour under approach traino conditions causing contact 82a of the third group of contacts to be operated to an open position relay WL is deenergized with the result that the warning signal indication W is displayed. Ii the train speed continues to increase and exceeds 17% miles per hour, contacts B2b and 02e are opened to deenergize magnet 6| and relay TR. Warning whistle is sounded and automatic brake application is effected at the end of the two and one-half seconds release period of timing relay TR unless the operator takes steps to shut off power and place the manual brake valve at the brake applying position so that the magnet valve MV is retained energized over its alternative circuit.

In case the vehicle enters an occupied track section and all decoding relays, A, R and L are released due to the absence of coded current, the slow cab signal unit is illuminated to display a slow indication and to indicate the maximum of 11 miles per hour. Magnet valve 6| and relays TR and WL are now energized over a fourth circuit path which includes the fourth group of contacts of the speed governor and front contact 99 of relay S. Since relay S is automatically picked up in response to this slow traffic condition and since the circuit for relay TR includes either back contacts 86 and 8B of relay S or front contacts 01 and 00 oi acknowledging relay SP the most restrictive indication must be acknowledged by the operator in order to energize relay TR land avoid an automatic brake application at the end of the two and one-half seconds slow release period of timing relay TR. It is to be noted that when relays A, R and L are all released due to this slow traic condition magnet valve 12 of the second unit of the warning magnet valve AMV is energized over the previously traced circuit to cause acknowledging whistle 'i0 to be sounded. To acknowledge this most restrictive indication, the operator depresses the acknowledging switch ACK to complete the pickup circuit of relay SP and then restores switch ACK to its normal position during the two and one-half seconds delay period. Relay SP when picked up to close iront contacts 8l and 89 retains the circuit for the timing relay TR closed. Hence after such acknowledgment of the most restrictive indication the vehicle can proceed at a speed not to exceed 11 miles per hour. In the event the speed of 10 miles per hour is reached under slow traiiic conditions so that contact 83a is opened the relay WL is released and warning signal W is displayed. If the train speed continues to increase and exceed 1l miles per hour, contacts B2b and 82C are opened to deenergize magnet 6| and relay TR. With magnet 6| deenergized the warning whistle 'H is sounded and power-oli switch PS is operated as previously explained. Timing relay TR is released at the end of its two and one-half seconds slow release period and magnet Valve MV is deenergized unless the operator takes steps to cornplete the alternative circuit for magnet valve MV by placing the master controller at the power oi position and placing the manual brake valve at the brake applying position.

It is to be pointed out that in the event magnet valve MV is deenergized and an automatic brake application is effected through brake application valve BA, magnet valve MV is not at once reenergized when the train speed has been reduced closing the contacts of the respective contact group of the speed governor because power ofi switch controller PS is opened due to the operation of valve BA and relay TR cannot be reenergized until controller PS is reclosed. Hence the operator must follow the same procedure used in suppressing an automatic brake application in order to release the automatic brake application. That is, the operator places the master controller at the power ofi position closing contacts |02 and HB3 and moves the manual brake valve to a brake application position operating suppression switch SR to close contacts |03 and |04. Magnet valve MV is then energized over its alternative circuit and brake valve BA is reset, after which the power oit controller PS is closed and relay TR reenergized.

In the event the vehicle moves from train control territory to nontrain control territory and in so doing passes over a track section which supplies the special 240 code rate, relay P is automatically picked up in response to operation of relay MR at the 240 code rate and relay P on picking up closing front contacts |05 and |00 completes its stick circuit by which it is retained energized subsequent to the train passing beyond the special track section and moving through nontrain control territory. When relay P is picked up the operating circuit for signal unit NS is completed and that unit is illuminated to display a purple color to indicate operation of the vehicle in nontrain control territory. Relay P on picking up to close front contacts I It and III also completes the alternative circuit by which relays TR and WL and magnet valve 6I are retained energized so that a vehicle may operate in nontrain control territory without the speed limits prescribed by the speed governor GV being enforced.

When the vehicle returns to train control territory the decoding relays A, R and L are energized according to the code rate of the track section entered, the cut-out relay P is deenergized and released and the apparatus is at once restored to its normal condition.

In the event it is desired to manually eiect the cut-out condition of the apparatus one member of the train crew actuates the cuteout switch CO at the same time another member of the train crew operates the acknowledging switch ACK, the cut-out switch being located remote from switch ACK. A pick-up circuit is thus formed for the cut-out relay P which circuit includes terminal B32, back contacts 2li, 3,6), 5I and 36 of relays A, R, SP and L, respectively, wire SI, contact 52 of acknowledging switch ACK when depressed, wire SPI, wire SP2, contact H3 of cutout switch CO when operated, wire PI, resistor |08, winding of relay P, wire NP, wire NPI, contact H4 of switch CO, wire NSP, and contact E3 of acknowledging switch ACK to terminal C. With cut-out relay P picked up it is then retained energized over its` previously described stick circuit. This operation of acknowledging switch ACK may also pick up acknowledging relay SP, `but the stick circuit for relay P would be retained complete over front contact Gil of relay SP. A lamp I I5 located at the cut-out switch CO is connected across wires SP2 and NPI and is illuminated in multiple with the winding of relay P While the acknowledging switch ACK and the cut-out switch CO are depressed and lamp H5 thus indicates to the train member operating cutout switch CO the position of the acknowledging switch ACK.

Although we have herein shown and described only one form of railway traino controlling apparatus embodying our invention, it is to be understood that various changes and modiications may be made therein within the scope of the appended claims without departing from the spirit and scope of our invention.

Having thus described our invention, what we claim is:

1. In a railway trailc controlling apparatus for use with train carried receiving means responsive to current coded at any one of a plurality of diierent code rates for energizing a particular decoding relay for each of said code rates to establish in turn a particular cab signal indication for each of the code rates, the combination comprising, a train operated speed governor having a contact for each of said code rates and each of which contacts is biased to a closed position and operated to an open position at speeds above a speed prescribed for the corresponding code rate, a slow release timing relay effective to control at its front contact a normal circuit for energizing a brake control magnet valve, a warning relay effective to control over its back contact a warning cab signal indication, a

warning magnet valve effective when deenergized to cause a warning whistle to sound; circuit means having a plurality of multiple circuit paths one for each of said code rates for energizing said timing relay, said warning relay and said warning magnet valve; each of said circuit paths including in series a front contact of the decoding relay and the speed governing contact of the same code rate as that with which the circuit path is associated, a manually operable suppression switch, and an alternative circuit including a contact of said suppression switch to energize said brake control magnet valve.

2. In railway traic controlling apparatus for use with train carried receiving means responsive to current coded at any one of three different code rates for selectively controlling three decoding relays and in turn establishing one of three cab signal indications according to the code rate of such current, the combination comprising, a train operated speed governor having three contacts one for each of said code rates and each of which contacts is biased to a closed position and operated to an open position at speeds above a speed prescribed for the corresponding code rate, a slow release timing relay to control over its front contact a brake control magnet valve, a warning relay to control over its back contact a warning cab signal indication, a whistle magnet valve to control when deenergized a warning air whistle; and circuit means having three multiple paths each of which paths includes a front contact of a selected one of said decoding relays and the contact of said speed governor which corresponds to the same code rate as the selected decoding relay for energizing said timing relay, said warning relay and said warning whistle magnet valve.

3. In railway trailic controlling apparatus for use with train carried receiving means responsive to current coded at any one of a plurality of different code rates for selectively controlling a corresponding number of decoding relays and in turn controlling a corresponding number of cab signal indications according to the code rate of such current, the combination comprising, a train operated speed governor having a plurality of contacts one for each of said code rates and each of which contacts is adjusted for operation at a speed prescribed for the corresponding code rate, a slow release timing relay, a brake control magnet valve controlled over a front contact of said timing relay, a warning relay, a warning cab signal unit controlled over a back contact of said warning relay, a warning magnet valve effective when deenergized to cause the sounding of a warning whistle; and circuit means having a plurality of parallel paths one for each of said code rates for energizing said timing relay, said warning relay and said Warning magnet Valve; and each of said circuit paths including in series a front contact of a particular decoding relay and the speed governor contact corresponding to the same code rate as said particular decoding relay.

4. In railway trac controlling apparatus for use with train carried receiving means responsive to current coded at any one of a plurality of different code rates for energizing a particular decoding relay for each of said code rates to establish in turn a particular cab signal indication for each of the code rates, the combination comprising, a train operated speed governor having a contact for each of said code rates and each of which contacts is biased to a closed position and operated to an open position at speeds above a lll speed prescribed for the corresponding code rate, a slow release timing relay effective to control over its front contact a normal circuit for energizing a brake control magnet valve, a warning magnet valve eiective when deenergized to cause a warning whistle to sound; circuit means having a plurality of multiple circuit paths' for energizing said timing relay and said Warning magnet valve in parallel and each of which circuit paths includes in series a front contact of a particular decoding relay and the speed governor contact for the code rate at which said particular decoding relay is energized, a manually operable suppression switch controller, and an alternative circuit including a contact of said controller for energizing said brake control magnet valve.

5. In railway trafliccontrollmg apparatus for use with train carried receiving means responsive to current coded at any one of three different code rates for energizing selected ones of three decoding relays and in turn governing three different cab signal indications according to the code rate, the combination comprising, a train operated speed governor having three groups of contacts one for each code rate, the contacts of each contact group adjusted for operation at a train speed prescribed for the associated code rate and with a prescribed speed differential between a rst and a second contact of the group, a warning relay adapted to govern over its contact a warning cab signal unit, a slow release timing relay adapted to govern over its contact a brake control magnet valve, a warning whistle magnet valve adapted when deenergized to cause a warning air whistle to sound, circuit means having three multiple circuit paths for energizing said warning magnet valve and said timing relay in parallel; each of said circuit paths including in series a iront contact of a selected one of said decoding relays, said second contact of the contact group of the speed governor correspending to the code rate at which said selected relay is energized and a resistor; and three circuit connections to connect said warning relay across said resistors and each of which circuit connections includes said first contact of the contact group a Contact of which group is interposed in the same multiple circuit path as the resistor.

6. In railway trado controlling apparatus for use with train carried receiving means responsive to current coded at any one of a plurality of diiierent code rates for energizing a particular decoding relay for each of said code rates to establish in turn a particular cab signal indication for each of the code rates, the combination comprising, a train operated speed governor having a contact for each of said code rates and each of which contacts is biased to a closed position and operated to an open position at speeds above a speed prescribed for the corresponding code rate, a slow release timing relay effective to control over its front contact a brake control magnet Valve, a warning electromagnetic device eiective when deenergized to cause a warning cab signal indication; circuit means having a plurality of multiple circuit paths one for each of said code rates to energize said timing relay and said electromagnetic device and each of which circuit paths includes in series a front contact of a particular decoding relay and the speed governor contact for the code rate at which said particular decoding relay is energized, a manually operable suppression switch controller, and

an alternative circuit including a contact of said suppression controller for energizing the brake control magnet valve.

7. In railway trairic controlling apparatus for use with train carried receiving means responsive to current coded at any one of three different code rates for energizing selected ones of three decoding relays according to the code rate and to release al1 such decoding relays in response to absence of such coded current for in turn governing four cab signal indications one for each of said code rates and a fourth one for the absence of coded current, the combination comprising, a train operated speed governor having four groups or contacts one group for each of said code rates and a fourth one for the absence of coded current, said contact groups set for operation at different preselected train speeds, a warning electromagnetic device eiective when deenergized to cause a warning cab signal indication, a slow release timing relay to control over its front contact a brake control magnet valve, Circuit means having three multiple paths each of which includes a front contact of a selected one of said decoding relays and a contact of the contact group for the code rate at which said selected decoding relay is energized to energize said electromagnetic device and said timing relay, circuit means including a back contact of each of said decoding relays and a contact of the contact group corresponding to the absence of coded current to energize said warning electromagnetic device, an acknowledging relay controlled over a back contact of each of said decoding relays and a contact of a manually operable acknowledging switch, and means including a front contact of said acknowledging relay to connect the timing relay to said last mentioned circuit means.

8. In railway traffic controlling apparatus for use with train carried receiving means responsive to current coded at a particular code rate for energizing a decoding relay to govern a correspending cabi signal indication, the combination comprising, a train operated speed governor having a contact group set for operation at a particular train speed with a prescribed speed diiferential between a rst and a second co-ntact of the group, a slow release timing relay adapted to control over its front contact a brake control magnet valve, a warning relay adapted to control over its back contact a warning cab signal indication, a Warning magnet valve adapted when, deenergized to actuate a warning air whistle, circuit means including a iront contact of said decoding relay, said second contact of said contact group of the speed governor and a resistor to energize said timing relay and said Warning magnet valve in parallel, and means including said rst contact of said contact group of the speed governor to connect said warning relay across said resistor.

9. In railway traiiic controlling apparatus for use with train carried receiving means responsive to current coded at a particular code rate for energizing a decoding relay to govern a corresponding cab signal indication, the combination comprising, a train operated speed governor having a contact group set for operation at a particular train speed with a prescribed speed differential between a rst and a second contact of the group, a slow release timing relay adapted to control over its front contact a brake control magnet valve, a warning relay adapted to control over its back contact a warning cab signal indication, a warning magnet valve eiective when energized to close a power off switch controller and when deenergized to open such power off switch controller and to actuate a warning air whistle; a control circuit including a front contact of said decoding relay, said second contact of s id control group of the speed governor and a resistor in series to energize said warning magnet valve; means including a nonnally closed contact of said power off switch controller to connect Said timing relay to said control circuit to energize said timing relay in multiple with the warning magnet valve, and means including said rst contact of said contact group in series with said second contact of the contact group to connect said warning relay across said resistor to energize the warning relay due to the voltage drop across said resistor.

l0. In railway trafiic controlling apparatus for use with train carried receiving means responsive to current coded at a particular code rate for energizing a decoding relay to govern a corresponding cab signal indication, the combination comprising, a train operated speed governor having a contact group set for operation at a particular train speed with a prescribed speed differential `between a rst and a second contact of the group, a slow release timing relay adapted to control over its front contact a brake control magnet valve, a warning relay adapted to control over itsback contact a warning cab signal indication, a warning magnet valve effective when energized to close a power oil switch controller and when deenergized to open such power off switch controller and to actuate a warning air whistle; a control circuit including a front contact of said decoding relay, said second contact of said control group of the speed governor and a resistor in series to energize said warning magnet valve; means including a normally closed contact of said power oi switch controller t connect said timing relay to said control circuit to energize said timing relay in multiple with the warning magnet valve, means including said rst contact of said contact group in series with said second contact of the contact group to connect said warning relay across said resistor to energize the warning relay due to the voltage drop across said resistor, a manually operable suppression switch controller, and an alternative circuit including a contact of said suppression switch controller to energize said brake control magnet valve independent of said timing relay.

l1. In railway trac controlling apparatus for use with train carried receiving means responsive to current coded at any one of a plurality of different code rates for energizing a particular decoding relay and in turn governing a particular cab signal indication in response to each of .said code rates, the combination comprising, a train operated speed governor having a contact group for each of said code rates, a slow release timing relay, a circuit including a iront contact of said timing relay to energize a brake control magnet valve, a warning relay, a Warning cab signal unit controlled over a Contact of said warning relay, a warning magnet valve, a warning whistle governed by said warning magnet valve and silent when the Warning magnet valve is energized and sounded when that magnet valve is deenergized,

circuit means having a plurality of multiple circuit paths one for each of said code rates for energizing said timing relay and said warning magnet valve in parallel; each of said circuit paths including a front contact of a particular decoding relay, a contact of the contact group of the speed governor for the code rate at which said particular decoding relay is energized and a resistor; and a plurality of circuit connections to connect said Warning relay across said resistors and each of which circuit connections includes a contact of the contact group having a contact interposed in the same circuit path as that resistor.

12. In railway traiic controlling apparatus for use with train carried receiving means responsive to current coded at any one of a plurality of different code rates corresponding to dilerent traffic conditions for energizing a plurality of decoding relays at a particular combination for each of said traic conditions, the combination comprising, a special cut-out decoding relay coupled to said receiving means for effective energization in response to current coded at a code rate different from said plurality of code rates, a stick circuit including a back contact of each of said plurality of decoding relays to energize said cut-out decoding relay, a special cut-out cab signal, and an operating circuit including a front contact of said cut-out decoding relay to operate said cut-out cab signal.

13. In railway traiic controlling apparatus for use with train carried receiving means responsive to current coded at any one of a plurality of different code rates corresponding to diiTerent trafc conditions for energizing a plurality of decoding relays at a particular combination for each of said traiic conditions for in turn selectively governing a cab signal to display a particular indication for each of said different traffic conditions, the combination comprising, a special cutout decoding relay coupled to said receiving means for eifective energization and picking up of that relay only in response to current coded at a code rate different from said plurality of code rates, a stick circuit including a back contact of each of said plurality of decoding relays for retaining said cut-out decoding relay picked up, an operating circuit including a back contact of each of said plurality of decoding relays and a back contact of said cut-out decoding relay to cause said cab signal to display a slow or most restrictive indication, and another operating circuit including a front contact of said cut-out decoding relay to cause said cab signal to display a cut-out indication.

14. In railway traffic controlling apparatus for use with train carried receiving means responsive to current coded at any one of a plurality of different code rates corresponding to different traiiic conditions for energizing a particular one oi a plurality lof decoding relays for each of said traffic conditions, the combination comprising, a special cut-out decoding relay coupled to said receiving means for effective energization in response to current coded at a code rate different from said plurality of code rates, a stick circuit including a back contact'of each of said plurality of decoding relays to energize said cut-out decoding relay, an electromagnetic device effective when deenergized to cause an automatic application of the train brakes, means including contacts oi said plurality of decoding relays effective to energize said electromagnetic device for each of said `traffic controlled combinations of such decoding relays, and an alternative circuit including a front Contact of said cut-out decoding relay to energize said electromagnetic device.

l5. In railway traffic controlling apparatus for use with train carried receiving means responsive to current coded at any one of a plurality of different code rates corresponding to different trafo conditions for energizing a particular one of a plurality of decoding relays for each of said trafhc conditions, the combination comprising, a special cut-out decoding relay coupled to said receiving means for effective energization in response to current coded at a code rate different from said plurality of code rates, a stick circuit including a back contact of each of said plurality of decoding relays to energize said cut-out decoding relay, a train operated speed governor having a contact for each of said plurality of code rates and each of which contacts is biased to a closed position and operated to an open position at speeds above a speed prescribed for the corresponding code rate, a slow release timing relay ei'lective to control over its front contact a brake control magnet valve, a warning magnet valve eiiective when deenergized to cause a warning whistle to sound, circuit means havin-g a plurality of multiple circuit paths for energizing said timing relay and said warning magnet valve in parallel, each of said circuit paths including in series a front contact of a particular decoding relay and the speed governor contact corresponding to the code rate at which that particular decoding relay is energized, and an alternative circuit including a front contact of said cut-out decoding relay to energize said warning magnet valve and said-timing relay.

16. In railway trafc controlling apparatus for use with train carried receiving means responsive to current coded at a particular code rate in response to a given traiic condition for energizing a traic controlled decoding relay for in turn causing a cab signal to display an indication corresponding to such traflic condition, the combination comprising, an electromagnetic device effective when deenergized to cause an automatic application of the train brakes, a i'lrst circuit including a iront contact of said decoding relay to energize said electromagnetic device, a cut-out decoding relay coupled to said receiving means for energization and picking up of such cut-out relay only in response to current coded at a rate different from said particular code rate, a stick circuit including a back contact of said traino controlled decoding relay to retain said cut-out decoding relay picked up, an operating circuit including a back contact of each of said decoding relays to cause said cab signal to display a slow indication, another operating circuit including a back contact of said traffic controlled decoding relay and a front lcontact of said cutout decoding relay to cause said cab signal to display a cut-out indication, and an alternative circuit including a iront contact of said cut-out decoding relay to energize said electromagnetic device.

17. In railway trailic controlling apparatus for use with train carried receiving means responsive to current coded at a particular code rate in response to a given traffic condition for energizing a traino controlled decoding relay for in turn causing a calo signal to display an indication corresponding to such traic condition, the combination comprising, an electromagnetic device eiiective when deenergized to cause an automatic application of the train brakes, a first circuit including a front contact of said decoding relay to energize said electromagnetic device, a cut-out decoding relay coupled to said receiving means for energization and picking up of such cut-out relay only in response to current coded at a rate different from said particular code rate, a stick circuit including a back contact of said traiiic controlled decoding relay to retain said cut-out decoding relay picked up, an acknowledging relay, a manually operable acknowledging switch, a pick-up circuit including a hack contact oi said tra-inc controlled decoding relay and a contact of said switch when operated to pick up said acknowledging relay, a stick circuit including a back contact oi each of said two decoding relays and a normally closed contact o said switch to retain said acknowledging relay picked up, a second circuit including a front contact of said acknowledging relay to energize said electromagnetic device, and a third circuit including a front Contact of said cut-out decoding relay to energize said electromagnetic device.

18. In railway traine controlling apparatus for use with train carried receiving means responsive to current coded at a particular code rate in response to a given trafc condition for energizing a trafiic controlled decoding relay for in turn causing a calo signal to display an indication corresponding to such traffic condition, the combination comprising, an electromagnetic device effective when deenergized to cause an automatic application of the train brakes, a first circuit including a front contact of said decoding relay to energize said electromagnetic device, an acknowledging relay, a manually operable acknowledging switch, an acknowledging whistle magnet valve effective when energized to cause an acknowledging whistle to sound, a circuit including a back contact of said acknowledging relay and a back contact of said decoding relay to energize said acknowledging whistle magnet valve, a pick-up circuit including a back contact of said decoding relay and a contact of said switch when operated to pick up said acknowledging relay, a stick circuit including a back contact of said decoding relay and a normally closed contact of said switch to retain said acknowledging relay picked up. and a second circuit including a front contact of said acknowledging relay to energize said electromagnetic device.

19. ln railway traic controlling apparatus for use with a train having the usual manual brake valve and provided with train carried receiving means responsive to current coded at a given rate for energizing a decoding relay, the combination V comprising, a brake control magnet valve eiiective when energized to control an automatic brake application valve to a release position and when deenergized to control such brake application valve to a brake application position, a suppression switch biased to an open position and operable to a closed position in response to a brake application position of the manual brake valve, a warning magnet valve effective when deenergized to cause the sounding of a warning whistle, a power off switch controlled to a closed position when said warning magnet valve is energized and to an open position when that magnet valve is deenergized and when said automatic brake application valve is. controlled to its brake application position, a timing relay, a normal circuit including a front contact of said timing relay to energize said brake control magnet valve, a control circuit including a front contact of said decoding relay to energize said warning magnet valve, means including a closed position contact of said power ofi switch to connect said timing relay to said control circuit to energize said timing relay in multiple with said warning magnet valve, and an alternative circuit including a closed position contact of said suppression switch to energize said brake control magnet valve.

20. In railway traino controlling apparatus for use with train carried receiving means responsive to current coded at a particular code rate in response to a given traino condition for energizing a trafc controlled decoding relay for in turn causing a cab signal to display an indication corresponding to such traiiic condition, the combination comprising, an electromagnetic device effective when deenergized to cause an automatic application of the train brakes, a rst circuit including a front contact of said decoding relay to energize said electromagnetic device, a cut-out decoding relay coupled to said receiving means for energization and picking up of such cut-out relay only in response to current coded at a rate diierent from said particular code rate, a stick circuit including a back contact of said traine controlled decoding relay to retain said cut-out decoding relay picked up, a rst and a second manually operable switch located on the train remote from each other, a special pick-up circuit including in series. a contact of each of said first and second manually operable switch to energize said cut-out relay, and an alternative circuit including a front contact of said cut-out decoding relay to energize said electromagnetic device. l

FRANK H. NICHOLSON. HAROLD W. BRYAN. 

